An investigation was launched after a dog walker discovered the remains at 4pm on New Year’s Day just a mile from the Royal Stud and less than two miles from the estate’s main residence.

The Queen and the Duke of Edinburgh, who are currently staying on the 20,000-acre (8,000-hectare) estate for their Christmas break, were informed of the discovery on Monday night.

The body was discovered shortly after the Royals attended a church service on Sunday.

Police said that a “detailed search” was being carried throughout the area of woodland in Anmer, near King’s Lynn, which is east of Sandringham House.

It remained unclear on Monday night how long the remains had been there, if they are in fact a body, if they had been identified, or the age of the victim or victims. The dog walker has also not been named.

A local resident, who did not want to be named, told The Daily Telegraph: “There is a heavy police presence even 24 hours after the discovery.

"You couldn't get very close to the site. Police said they expected to be there tomorrow."

A Norfolk Police spokesman said: “Detectives from Norfolk Constabulary have launched an investigation following the discovery of human remains in an area of woodland at Anmer, near King’s Lynn.

“The remains were found by a member of the public who reported the incident to police on Sunday January 1 shortly after 4pm. The area has been sealed off and a detailed search is currently being carried out.”

Police declined to comment further or release any details about the remains. No indication of the age or nature of the remains was given

The details emerged just days after the Duke, 90, left Papworth Hospital, Cambridgeshire, where he was treated for a blocked artery after suffering chest pains.

The Duke’s heart scare forced him to miss the annual celebrations, including the annual Boxing Day shoot.

He was airlifted to hospital from Sandringham on December 23 and kept under observation for four nights after undergoing the “minimally invasive procedure” of coronary stenting, which was declared a success.

The Queen, who makes it her official base until February, was seen riding on the estate on Monday morning.

The 85-year-old year-old wore only a head scarf and the hood of her long blue waxed jacket for protection as she rode a chestnut coloured horse.

She emerged in the winter sunshine a few minutes later on horseback, accompanied by a smartly-dressed male groom on a white horse who was wearing a proper black riding hat in case he fell off.

Sandringham has served as a private residence for Royal Family since 1862. King George V, the queen's grandfather, once called "dear old Sandringham... (the) place I love better than anywhere in the world".

Around half of the estate is let to farm tenants, with much of the remainder used for forestry.

In October The Daily Telegraph disclosed that the remains of an American man had been lying near Buckingham Palace for years.

Robert James Moore sent hundreds of letters to the Queen and was driven by his obsession to set up home within sight of Buckingham Palace, on an island in St James’s Park.

But somehow his camp that he set up by went unnoticed until a tree surgeon uncovered the remains of his body in October, as many as three years after his death.